1. Field of the Invention
The present invention relates generally to landing gear for airplanes. More specifically, but without limitation thereto, the present invention relates to airplanes which have landing gear that folds upon retraction.
2. Discussion of the Background Art
Airplane landing gear generally is designed such that the landing gear is retracted into the plane through a wheel well door which opens and closes with the extraction and retraction of the landing gear. The wheel well opening on conventional systems is longer than that of the landing gear and thus there is no problem retracting the landing gear up into the wheel well after take off. However, some airplanes have the need for a landing gear which is longer than the wheel well opening. Redesign of the wheel well to accommodate a lengthened landing gear may not be a viable option due to the increased cost of redesigning the wheel well.
One solution to this problem, as shown in the prior art, is to have a landing gear with sliding rods which shorten upon retraction. For example, U.S. Pat. No. 5,429,323 shows a landing gear system with multiple sliding rods. As the landing gear is retracted the sliding rods shorten enabling the landing gear to fit inside of the wheel well. However, this is a very complex solution which has limited access for repairs and inspection. Additionally, the landing gear is limited in the amount of length in which it can shorten by the sliding rods.
Thus there is a need for landing gear that eliminates the problems discussed above, as well as other problems.
The present invention advantageously addresses the needs above as well as other needs by providing an airplane landing gear that folds upon retraction.
In one embodiment, the present invention includes a landing gear for an airplane comprising a first support member; a second support member coupled to the first support member through a first pivot point, and a third support member coupled to the second support member through a second pivot point; wherein the second support member folds back upon the first support member as the landing gear is retracted into a wheel well; wherein the third support member folds back upon the first support member and moves aft as the landing gear is retracted into the wheel well.
In another embodiment, the invention can be characterized as landing gear for an airplane comprising: a plurality of connectors for mounting the landing gear to an airplane; a support structure coupled to the plurality of connectors; a shock strut coupled to the support structure through a bell crank; and a plurality of wheels coupled to the shock strut; wherein the bell crank rotates moving the shock strut aft during retraction of the landing gear.
In yet another embodiment, the invention advantageously includes a method of retracting landing gear comprising the steps of actuating a hydraulic member; causing a first support member to rotate in a first direction about a first pivot point in response to actuating the hydraulic member; causing a second support member to rotate in a second direction about a second pivot point in response to actuating the hydraulic member; and causing a third support member to rotate in the second direction about a third pivot point; causing the third support member to move aft during the rotation about the third pivot point.
In a subsequent embodiment, the invention advantageously includes a landing gear for an airplane comprising a plurality of connectors coupled to the airplane; a first support member coupled to at least one of the plurality of connectors; a second support member pivotally coupled to the first support member; a third support member pivotally coupled to the second support member; a wheel coupled to the second support member; a bell crank coupled to the third support member; and a link system coupled to the bell crank; wherein the second support member folds back upon the first support member and moves aft upon retraction of the landing gear into the airplane.